/in/foo.cc: In function 'int main()':
/in/foo.cc:42:69: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
                 if (num[a][b]<num[i][j]+1 || num[a][b]==num[i][j]+1 && ans[a][b]>ans[i][j]+z[k]){
                                              ~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~